2 Answers

Unresponsive Keys in the same line or another pattern point to a defective inner mat / active layer. Don't know the right term for it. This is the rubber (sandwiched) mat with the microswitches and connector / cable. Unfortunately i never found a way to salvage those, neither by disassemling (impossible) or cleaning.

Usually this points to a liquid damage. I don't think you have another chance than purchasing another keyboard. They shoudn't be too expensive, though.

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